不同质量浓度低聚果糖和低聚半乳糖对发酵乳品质的影响

研究不同质量浓度低聚果糖和低聚半乳糖对发酵乳在发酵期和贮藏期内乳中菌落活菌数、滴定酸度和黏度的影响。结果表明：在发酵期低聚果糖（QHT-90 FOS）对发酵乳中乳酸菌活菌数的增殖作用要显著高于低聚半乳糖（QHT-60 GOS），在QHT-90 FOS质量浓度为1.5 g/100 mL的样品中，12 h时瑞士乳杆菌（Lactobacillushelveticus）MB2-1活菌数可达到4.44×109 CFU/g，而不同质量浓度和结构的低聚果糖和低聚半乳糖对样品滴定酸度和黏度的影响差异不显著；此外在4 ℃发酵乳贮藏期间，QHT-90 FOS对L. helveticus MB2-1有一定保护作用，在QHT-90 FOS质量浓度为1.5 g/100 mL的样品中，贮藏14 d后，活菌数仅减少11.90%，而滴定酸度基本不变，产品黏度保持在9 000 mPa·s。

Effects of Fructooligosaccharide and Galactooligosaccharide at Different Concentrations on the Quality of Fermented Milk

This work studied the effects of fructooligosaccharide (QHT-90 FOS) and galactooligosaccharide (QHT-60
GOS) with various concentrations on the viable count of Lactobacillus helveticus MB2-1, titratable acidity and viscosity
of fermented milk during fermentation and storage. The results showed that QHT-90 FOS had a better ability to increase
the proliferation of Lactobacillus in fermented milk than QHT-60 GOS. When the concentration of QHT-90 FOS was
1.5 g/100 mL in 12-hour fermented milk, the viable count of L. helveticus MB2-1 reached 4.44 × 109 CFU/g.
Oligosaccharides with different structures had similar effects on titratable acidity and viscosity of different samples.
QHT-90 FOS had the ability to protect L. helveticus MB2-1. Under the storage condition of 4 ℃, the viable count of
L. helveticus MB2-1 decreased by only 11.90%. After 14 days of storage, the titratable acidity remained unchanged, and the
viscosity stayed at a high level of 9 000 mPa·s.